Exhaust system for hood structure



Dec. 10, 1968 J. R. SCHEEL 3,415,179

EXHAUST SYSTEM FOR HOOD STRUCTURE Filed Oct. 12, 1966 5 Sheets-Sheet l INVIENTOR.

JOHN R. SCHEEL F18. 2 BY ATTORNEYS Dec. 10, 1968 J. R. SCHEEL 3,415,179

7 EXHAUST SYSTEM FOR HOOD STRUCTURE Filed Oct. 12, 1966 3 Sheets-Sheet 2 INVENTOR. JOHN R SCHEEL 14ml, GMHIM ATTORNEYS Dec. 10, 1968 .1. R. SCHEEL 3,415,179

EXHAUST SYSTEM FOR HOOD STRUCTURE Filed Oct. 12. 1966 3 Sheets-Sheet 3 l 59 67 s4 64 Q Z 7| e5 H I 65 l 5 V INVENTOR,

JOHN R. SCHEEL Hood, GuAHI'J-AK ATTORNEYS United States Patent 3 415,179 EXHAUST SYSTEM FOR HOOD STRUCTURE John R. Scheel, Anderson, Ind., assignor, by mesne assignments, to Hawley Manufacturing Corporation, Indianapolis, Ind., a corporation of Indiana Filed Oct. 12, 1966, Ser. No. 586,107 11 Claims. (Cl. 98-115) ABSTRACT OF THE DISCLOSURE A ventilation system comprises a hood designed to cover the open top of a cylindrically-shaped furnace which is supported for rocking movement about a horizontal axis. The hood is arranged to rock with the furnace. An upper duct and a lower duct are arranged to rock with the hood and communicate, respectively, with the upper region of the interior of the hood and with an annular duct disposed about the inner wall of the hood just above the open top of the furnace. Said annular duct communicates with the interior of the hood to receive vapors emanating from the furnace. The upper duct and the lower duct communicate with exhaust through a swivel connection coaxial with the said horizontal axis, whereby the hot gases evolved in the furnace are more effectively exhausted to prevent overheating and consequent warping of the hood.

The present invention relates to a ventilation system, and more particularly to the means and methods for providing a ventilation system for exhausting fumes and smoke emanating from a melting furnace.

The ventilation system of the present invention is ideally suited for use in conjunction with an open topped, generally cylindrically-shaped furnace of the type arranged to be pivoted about a horizontal axis. The ventilation system comprises a hood proportioned and arranged to cover such a furnace and to pivot therewith about the pivot axis of said furnace. In the ventilation system of the present invention, an upper and lower duct are connected to the hood. The upper duct communicates with and exhausts an upper portion of the hood and the lower duct communicates with and exhausts an annular duct disposed about the inner wall of said hood just above the opening of the furnace. The annular duct is arranged to communicate with the interior of the hood and to receive vapors emanating from the furnace. By providing an upper and lower duct and a lower, inner duct as described, the hot fumes emanating from the material in the furnace are more rapidly removed from the hood, thereby reducing the surface temperature of the hood to minimize warping. Thus, by mimimizing warping of the hood, the present invention has solved a long standing problem in the furnace ventilation art.

It is an object of the present invention, therefore, to provide a ventilation system for more rapidly and efficiently removing the vapors emanating from any source, as, for instance, from a pool of molten metal in a furnace, which must, in most cases, be discharged at a point where their noxious character will be rendered innocuous.

Another object of the present invention is to provide a hood proportioned and arranged to cover a furnace, said hood having an inner duct disposed therein and arranged to communicate with the interior of said hood, said inner duct and said hood being exhausted by separate ducts to more rapidly and eiiiciently scavenge the fumes emanating from the material in the furnace.

Still another object of the present invention is to provide such a hood mounted on a furnace arranged to be pivoted about an axis, said hood being arranged to be pivoted about said axis with said furnace.

3,415,179 Patented Dec. 10, 1968 A further object of the present invention is to provide such a hood for covering a pivotally mounted furnace having a pouring spout disposed on an upper lip thereof, said hood having a hingedly mounted door disposed between a pair of side panels and above said pouring spout, said door being arranged to remain vertical when said hood and said furnace are pivoted, thereby providing, in combination with said side panels, a duct opening into said hood and arranged to receive vapors emanating from material being poured from said pouring spout.

Further objects of the present invention will appear as the description proceeds.

To the accomplishment of the above and related objects, the present invention may be embodied in the form illustrated in the accompanying drawings, attention being called to the fact, however, that the drawings are illustrative only, and that change may be made in the specific construction illustrated and described, so long as the scope of the appended claims is not violated.

In the drawings:

FIG. 1 is a perspective view of the ventilation system of the present invention and showing said system operatively arranged to ventilate an open topped, generally cylindrically-shaped furnace of the type arranged to be pivoted about a horizontal axis;

FIG. 2 is a front elevation view of the ventilation system shown in FIG. 1;

FIG. 3 is a top elevation view of the ventilation system shown in FIG. 1;

FIG. 4 is a fragmentary, exploded perspective view showing an opening for charging the furnace in the back of the hood of the ventilation system and a door to cover said opening;

FIG. 5 is a sectional view taken from FIG. 2 generally along the line 55 and illustrating a duct disposed about the inner wall of the aforementioned hood;

FIG. 6 is a sectional view taken from FIG. 3 generally along the line 66 and illustrating a swing-out door for providing a duct opening into said hood and arranged to receive vapors emanating from material being poured from the furnace;

FIG. 7 is a sectional view similar to FIG. 6 except the furnace and hood are tilted and the swing-out door is opened to receive vapors emanating from the material being poured from the furnace; and

FIG. 8 is a sectional view taken from FIG. 5 generally along the line 88 and illustrating the structure and function of the duct disposed inside the hood, the door for the charging opening having been removed.

Referring now to the drawings, the structure of an illustrative embodiment of the present invention can be visualized in conjunction with the following description.

The ventilation system of the present invention, indicated generally by the reference number 10, is ideally suited for use in conjunction with an open topped, generally cylindrically-shaped furnace, of the type indicated generally by the reference number 11. The furnace 11 is pivotally mounted about a horizontal axis 12. The ventilation system 10 comprises a hood 13 proportioned and arranged to cover the furnace 11 and to pivot about the axis 12 with said furnace. In FIG. 1, it can be seen that the furnace 11 is pivotally mounted about the axis 12 by means of a pair of arms 14 and 15, each of which has one end rigidly connected to the furnace 11 and its other end pivotally mounted about trunnion 16 or 17. The connection between the arms 14 and 15 and the furnace 11 is not shown in any view. The trunnions 16 and 17 are coincident with the axis 12 and retained in supports, indicated by the reference number 18. In FIGS. 1, 2, 3, and 5 it can be seen that the hood 13 is provided with a pair of arms 19 and 20 which are pivotally mounted about the trunnions 16 and 17, respectively. The arms 3 19 and are rigidly connected to the hood 13 as shown at 19' and 20 in FIG. 2.

As seen in FIG. 3, angle brackets, indicated by the reference number 21, are provided on the hood 13 for connecting the hood to the furnace 11. The angle brackets 21 are bolted to similar angle brackets, not shown in any view, on the furnace 11.

There is an upper duct 22 and a lower duct 23 connected between the hood 13 and a common duct 24. As seen in FIGS. 1, 2 and 3, the common duct 24 is swivelly connected about the axis 12 to a chamber 25. The swivel connection between the duct 24 and the chamber 25 is indicated generally by the reference number 26 in FIGS. 2 and 3. Swivel connections for ventilating ducts are well known in the art and need not be discussed in this description.

From the discussion thus far, it is clear that the furnace 11, hood 13, upper duct 22, lower duct 23 and common duct 24 are all arranged to be pivoted in the direction of the arrow 26', shown in FIG. 1, about the axis 12.

It can be seen, that the furnace 11 is provided with a pouring spout 27 formed in its upper, front lip. The hood 13 is provided with a door 28 disposed above the pouring spout 27 and guarding a port 28 in a side wall of the hood. There is a pair of vertically and outwardly extending side panels 29 and 30, one disposed on each side ofthe door 28. The door 28 is hingedly mounted at its uppermost portion about an axis substantially parallel to the axis 12 by means of hinge pins 31 which are journalled in the side panels 29 and as shown in FIG. 2. In its closed position, the door 28 is held against the flange 32 of an angle bracket 33 arranged on each side panel 29 and 30 as shown in FIGS. 5, 6 and 7. The door 28 is held against the flange 32 by a bar 34 which is received in a generally L-shaped slot 35 provided in each of the side panels 29 and 30 as shown clearly in FIGS. 6 and 7. The bar 34 is in a locking position against the door 28 when the bar 34 is in the closed end of the slots 35. When the bar 34 is removed from the L-shaped slots 35, the door 28 is free to move with respect to the flange 32 as shown in FIG. 7. The bar 34 is carried in a pair of brackets 36 fastened to the door 28 and designed to permit appropriate movement of the bar as it enters and leaves the slots 35.

There is a panel 37 disposed between the tops of the side panels 29 and 30 to provide a cover for the space between said panels. The panel 37 is hingedly mounted to the side panels 29 and 30 by means of hinge pins 38 which are journalled in said side panels. In FIGS. 6 and 7, it can be seen that the panel 37 is provided with a front, vertical flange 39 and a pair of side, vertical flanges 40, only one of which is seen in FIGS. 6 and 7. The hinge pins 38 extend through openings 41 in the flanges 40. A coiled spring 42, only one of which is shown in FIGS. 6 and 7, is connected between each side of the panel 37 and its associated side panel 29 and 30 to maintain the panel 37 closed against the tops of the side panels 29 and 30.

In FIGS. 6 and 7, it can be seen that there is a baffle 43 disposed below the opening between the hood 13 and the panel 37.

The door 28 and the side panels 29 and 30 define a duct opening into the hood 13 through port 28' when the door 28 is open and the hood 13 and furnace 11 are tilted as shown in FIG. 7. The duct defined by the door 28 and side panels 29 and 30 receives vapors, indicated by the arrows 44, emanating from fluid being poured from the pouring spout 27 and conducts said vapors into the exhausted hood 13.

There is a removable door 45 arranged to cover an opening 46 is the back of the hood 13, as shown in FIGS. 3 and 4. The opening 46 is provided to permit charging of the furnace. The door 45 is provided with handles 47 and a pair of lugs 48 which are rigidly fastened thereto and arranged to extend out on each side thereof. The

lugs 48 are received in brackets 49 fastened to the hood 13 and arranged to hold the door 45 against the hood to close the opening 46.

There is a sampling duct 50 extending through the hood 13 as shown in FIGS. 2, 3 and 5 to permit sampling of material in the furnace 11. Closure means (not shown) may be provided for said sampling duct if desired.

The hood 13 is provided with a removable top 51 which permits top loading of the furnace 11. The removable top 51 is supported on an annular support bracket 52 fastened to the inner wall of the hood 13 indicated by dashed lines in FIG. 3. The top 51 is held down by means of a pair of hold down bars 53 which extend across the top of the hood 13. The hold down bars 53 are provided with end slots 53 for receiving bolts 54 which are swivelly connected to the hood 13. Wing nuts 55 are arranged on the bolts 54 to secure the bars 53. A lifting ring 56 is connected to the center of the top 51 to provide a means for lifting the top from the hood 13.

A plurality of lifting rings, indicated by the reference number 57, is provided for lifting the entire ventilation system 10 from the furnace 11.

The lower duct 23 is connected to the hood 14 so as to communicate with an inner duct 58 which is arranged inside the hood 13. The inner duct 58, which is seen in FIGS. 5 and 8, is annular in shape and is disposed about the periphery of the opening of the furnace 11. In the illustrative embodiment of the present invention, the annular, inner duct 58 has closed ends 59 spaced apart to provide clearance for charging the furnace 11 through the opening 46. The inner duct 58 is in communication with the interior of the hood 13 through an elongated slot, indicated by the reference number 60 in FIG. 8, which extends about the innermost, side wall of said duct. There is a plurality of support brackets 61 arranged to support the top wall 62 of the duct 58 on the innermost, side wall of said duct. The support brackets 61 do not significantly interfere with passage of vapors into the duct 58. The top wall 62 of the duct 58 extends inwardly beyond the innermost, side wall of the duct 58 to provide a baffle above the elongated slot 60. A stiffener, indicated by the reference number 63, is welded or otherwise fastened to the top wall 62.

The hood 13 is supported on the furnace 11 by a plurality of support brackets 64, seen in FIGS. 5 and 8. The support brackets 64 are supported by the outer wall of the furnace 11 and and annular platform 65 extending about the interior of the uppermost portion of the wall 11. In FIG. 8, it can be seen that the internal diameter of the hood 13 is substantially greater than the external diameter of the furnace L1 and that the support brackets 64 are arranged to concentrically support the hood 13 on the furnace 11. It can be seen, therefore, that there is an annular opening indicated by the reference number 65, which permits air flow into the furnace 11. The height of the support brackets 64 is sufiicient to permit air entering the opening 65 to reach the interior of the furnace 11.

In operation of the ventilation system l0, the inner duct 58 is exhausted through the lower duct 23, common duct 24 and chamber 25. There is an exhaust pump 66, of the kind normally used in ventilation systems, connected to the chamber 25. The upper portion of the hood 13 is exhausted through the upper duct 22, common duct 24 and chamber 25.

Referring to FIG. 8, it can be seen that air enters the enclosure formed by the hood 13 and furnace 11 through the opening 65 and the space provided by the support brackets 64. The entering air is indicated by the arrows 67. When the furnace 11 is full of molten metal, the air entering the opening 65 mixes with the fumes and vapors emanating from the molten metal to produce combustion, thereby minimizing the amount of smoke produced by the molten metal. The lower portion of the hood 13 is exhausted by the duct 58 which draws the combustion product in the direction of the arrows 68. The combustion product which is not drawn off through the duct 58 moves in the direction of the arrows 69 to the upper portion of the hood 13 where it is exhausted through the upper duct 22.

I claim as my invention:

1. In combination with an open topped, generally cylindrically-shaped furnace of the type arranged to be pivoted about a horizontal axis, a ventilation means comprising a hood proportioned and arranged to cover said furnace and to pivot therewith about said axis, means for supporting said hood above said furnace, said supporting means being arranged to provide an annular spacing between said hood and said furnace for admitting air to said furnace, an annular duct disposed about the inner wall of said hood just above said furnace, said annular duct having a perimetrally-extending opening relative to the wall of said hood for receiving vapors emanating from said furnace, first duct means having one end connected to said annular duct and its other end connected to second duct means, third duct means having one end connected to said hood and communicating with an upper portion thereof and its other end connected to said second duct means, said second duct means being swivelly connected about said horizontal axis to means providing a chamber, and means for exhausting said chamber.

2. The combination of claim 1 including a removable door for charging said furnace, said door guarding a port opening into said hood just above said furnace.

3. The combination of claim 1 wherein there is an opening in said hood and a door covering said opening, said door being hingedly mounted about an axis at its uppermost portion, said hinge axis of said door being generally parallel to said pivot axis to permit said door to remain vertical when said hood is pivoted, vertically and outwardly extending panels on opposite sides of said opening, a panel disposed between the tops of said side panels to provide a cover for the space between said side panels, said door and said side panels defining a duct communicating through said opening into said hood and arranged to receive vapors emanating from material being poured from said furnace, and means for releasably holding said door closed.

4. The combination of claim 3 wherein said panel connected between said side panels is hingedly mounted about an axis substantially parallel with said hinge axis of said door, and including resilient means for maintaining said panel closed against the tops of said side panels.

'5. The combination of claim 1 including an access duct extending through said hood and said annular duct to permit sampling of material in said furnace.

6. The combination of claim 1 wherein said hood has a greater internal diameter than the external diameter of said furnace and wherein said supporting means are arranged to concentrically support said hood on said furnace so as to have the lowermost portion of said hood overlap the uppermost portion of said furnace, thereby providing said annular spacing for admitting air to said furnace.

ranged to be pivoted about an axis, a ventilation means comprising a hood proportioned and arranged to cover an opening in said receptacle and to pivot therewith about said axis, means providing a passage for admitting air to said recepiable, first and second duct means, said first duct means having one end connected to said hood and its other end connected to said second duct means, third and fourth duct means, said third duct means having one end connected to said fourth duct means and its other end connected to said second duct means, said fourth duct means being disposed inside said hood intermediate said opening and the portion of said hood having said first duct means connected thereto, said fourth duct means extending about the perimeter of said opening, said fourth duct means being in communication with the interior of said hood and arranged to receive vapors emanating from said receptacle, means providing a chamber, said second duct means being swivelly connected about said axis to said means providing a chamber, and means for exhausting said chamber, thereby exhausting said hood and said fourth duct means.

8. The combination of claim 7 wherein said fourth duct means has an opening extending longitudinally thereabout, said opening receiving vapors emanating from said receptacle.

9. The combination of claim 8 'wherein said opening extends about an innermost wall of said fourth duct means.

10. The combination of claim 7 wherein said means providing a passage for admitting air to said receptacle comprises spacers for mounting said hood on said receptacle.

11. In combination with a receptacle, a ventilation means comprising a hood proportioned and arranged to cover an opening in said receptacle, pump means, first duct means connected between said pump means and said hood, an annular duct disposed about the inner wall of said hood between said opening and the portion of said hood having said first duct means connected thereto, said annular duct having a perimetrally-extending opening in communication with the interior of said hood and arranged to receive vapors emanating from said receptacle, and duct means connected between said annular duct and said pump means, said pump means being effective to exhaust said hood and said annular duct means.

References Cited UNITED STATES PATENTS 2,862,701 12/1958 McFeaters 98-115 XR 2,908,737 10/1959 Dominicis 98-115 XR 3,154,406 10/1964 Allard 266-35 XR 3,205,810 9/1965 Rosenar 98-115 3,269,716 8/1966 Walker 266-35 FOREIGN PATENTS 198,255 9/ 1938 Switzerland.

ROBERT A. OLEARY, Primary Examiner.

M. A. ANTONAKAS, Assistant Examiner.

US. Cl. X.R. 266-35 

